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Circular Ring Slim gets trim to battle Oura for smart ring crown

Look out Oura! Smart ring rival Circular is back with what it attests is not only the world’s thinnest and lightest health ring, but the slimmest and lightest wearable per se.

The follow-up to the Circular Ring Pro enters an increasingly competitive smart ring market, but distinguishes itself at just 2.2mm thick, while barely registering on the scales at 2 grams. However, cutting the footprint doesn’t mean any of the precision sensors for health and fitness tracking are absent.

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The Slim model includes the three-axis accelerometer for activity tracking, a surface temperature sensor, PPG sensors, and LED arrays to track metrics like heart rate, breathing rate, heart rate variability, and blood oxygen levels.

It’ll also track circadian rhythm, sleep stages, sleep disturbances, as well as sleep/wake times. The company also promises the temperature variance readings can help inform immune system health.

The Circular Ring Slim only needs to be charged every six days and will store data for 20-days before it needs to be transferred to the companion smartphone app.

Circular ring slim

Beyond the metrics tracked and battery life, the Slim model is also a little more interactive. The button is gone and replaced by a haptic navigation interface. Users will be able to tap anywhere around the ring to interact with the device, while vibrating alerts provide feedback across various features including a new smart alarm, and to guide breathing and meditation exercises.

And it wouldn’t be a tech launch these days without AI playing a major role in proceedings. The Circular Ring Slim teams with Kira+ which is “an AI-powered conversational health and wellness assistant.”

Over 14-days the assistant gets to know the wearer, studies their habits, establishes biometric base markers and asks regular questions in order to provided personalised recommendations. You’ll get this without incurring a subscription fee, and the Circular app data can be integrated within Google Fit and Apple Health.

The Circular Ring Slim is available to pre-order now for £199 and will officially go on sale on December 15. By preordering you get a discount on the £225 asking price.

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